Is the incidence of malignancy increased in patients with sarcoidosis? A systematic review and meta‐analysis

A possible causal relationship between sarcoidosis and malignancy has been the subject of debates for decades. To better understand this association, we conducted a systematic review and meta‐analysis of cohort studies that reported relative risk, hazard ratio or standardized incidence ratio with 95% confidence interval (CI) comparing the incidence of malignancy in patients with sarcoidosis versus non‐sarcoidosis participants. Pooled risk ratios (RR) and 95% CI were calculated using a random‐effect, generic inverse variance methodology. Five studies were identified and included in our data analyses. The pooled RR of malignancy in patients with sarcoidosis was 1.21 (95% CI: 1.04–1.40). However, when we performed a sensitivity analysis that included only studies that compared the incidence of malignancy after the first year of the diagnosis of sarcoidosis with the incidence of malignancy after the first year of index date for non‐sarcoidosis controls, the pooled risk ratio decreased and did not reach statistical significance (RR 1.13, 95% CI: 0.97–1.32). Furthermore, analysis for publication bias has suggested that publication bias in favour of positive studies may be present. In conclusion, after accounting for possible detection bias and publication bias, there does not appear be a significant association between sarcoidosis and malignancy.     

Does continuous positive airway pressure therapy benefit patients with coronary artery disease and obstructive sleep apnea? A systematic review and meta‐analysis

The prevalent co‐morbidity of coronary artery disease (CAD) and obstructive sleep apnea (OSA) has attracted great interest. However, effects of continuous positive airway pressure (CPAP) in patients with OSA and CAD for cardiovascular outcomes and deaths are still controversial. Usage of CPAP among patients with CAD and OSA could decrease the risk of cardiovascular events and death in adults. PubMed, EMBASE, Web of science, and Cochrane Library were systematically searched. Studies that described association of CPAP treatment with cardiovascular events in CAD and OSA patients were included. The main outcome was the major adverse cardiovascular events (MACE), including all‐cause death, cardiovascular death, myocardial infarction (MI), stroke, and repeat revascularization. Summary relative risks (risk ratios [RRs]) and 95% confidence intervals (CIs) of outcomes were pooled and heterogeneity was assessed with the I² statistic. Nine studies enrolling 2590 participants with OSA and CAD were included and extracted data. There was significant association of CPAP with reduced risk of MACE (RR, 0.73, 95% CI [0.55, 0.96]), particularly among those with AHI less than 30 events/h (RR, 0.43, 95% CI [0.22, 0.84]). Similarly, the same result was found in all‐cause death (RR, 0.66, 95% CI, [0.46, 0.94]) and cardiovascular death (RR, 0.495, 95% CI [0.292, 0.838]). Our data suggested that CPAP usage, compared to usual care, was associated with reduced risks of cardiovascular outcomes or death in patients with OSA and CAD, particularly in the subgroup with AHI less than 30 events/h, which still needs further studies to confirm.     

Peripheral venous and arterial blood gas analysis in adults: are they comparable? A systematic review and meta‐analysis

Peripheral venous blood gas (PVBG) analysis is increasingly being used as a substitute for arterial blood sampling; however, comparability has not been clearly established. To determine if the pH, PCO₂ and PO₂ obtained from PVBG analysis is comparable with arterial blood gas (ABG) analysis. A search was conducted of electronic databases as well as hand‐searching of journals and reference lists through December 2012 to identify studies comparing PVBG with ABG analysis in adult subjects. A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. A meta‐analysis using a random effects model was used to calculate the average difference (bias) and the limits of agreement for the venous and arterial pH, PCO₂ and PO₂. A total of 18 studies comprising 1768 subjects were included in the meta‐analysis. There was considerable heterogeneity between studies with I² approaching 100%. There was little difference between the pH obtained from the PVBG and the ABG, with the arterial pH typically 0.03 higher than the venous pH (95% confidence interval 0.029–0.038). The venous and arterial PCO₂ were not comparable because the 95% prediction interval of the bias for venous PCO₂ was unacceptably wide, extending from ?10.7 mm Hg to +2.4 mm Hg. The PO₂ values compared poorly, the arterial PO₂ typically 36.9 mm Hg greater than the venous with significant variability (95% confidence interval from 27.2 to 46.6 mm Hg). PVBG analysis compares well with ABG analysis for pH estimations in adults but not to the PCO₂ or PO₂. These differences are sufficiently large to be of clinical significance.     

Do ketogenic diets really suppress appetite? A systematic review and meta‐analysis

Very‐low‐energy diets (VLEDs) and ketogenic low‐carbohydrate diets (KLCDs) are two dietary strategies that have been associated with a suppression of appetite. However, the results of clinical trials investigating the effect of ketogenic diets on appetite are inconsistent. To evaluate quantitatively the effect of ketogenic diets on subjective appetite ratings, we conducted a systematic literature search and meta‐analysis of studies that assessed appetite with visual analogue scales before (in energy balance) and during (while in ketosis) adherence to VLED or KLCD. Individuals were less hungry and exhibited greater fullness/satiety while adhering to VLED, and individuals adhering to KLCD were less hungry and had a reduced desire to eat. Although these absolute changes in appetite were small, they occurred within the context of energy restriction, which is known to increase appetite in obese people. Thus, the clinical benefit of a ketogenic diet is in preventing an increase in appetite, despite weight loss, although individuals may indeed feel slightly less hungry (or more full or satisfied). Ketosis appears to provide a plausible explanation for this suppression of appetite. Future studies should investigate the minimum level of ketosis required to achieve appetite suppression during ketogenic weight loss diets, as this could enable inclusion of a greater variety of healthy carbohydrate‐containing foods into the diet.     

What childhood obesity prevention programmes work? A systematic review and meta‐analysis

Previous reviews of childhood obesity prevention have focused largely on schools and findings have been inconsistent. Funded by the US Agency for Healthcare Research and Quality (AHRQ) and the National Institutes of Health, we systematically evaluated the effectiveness of childhood obesity prevention programmes conducted in high‐income countries and implemented in various settings. We searched MEDLINE®, Embase, PsycINFO, CINAHL®, ClinicalTrials.gov and the Cochrane Library from inception through 22 April 2013 for relevant studies, including randomized controlled trials, quasi‐experimental studies and natural experiments, targeting diet, physical activity or both, and conducted in children aged 2–18 in high‐income countries. Two reviewers independently abstracted the data. The strength of evidence (SOE) supporting interventions was graded for each study setting (e.g. home, school). Meta‐analyses were performed on studies judged sufficiently similar and appropriate to pool using random effect models. This paper reported our findings on various adiposity‐related outcomes. We identified 147 articles (139 intervention studies) of which 115 studies were primarily school based, although other settings could have been involved. Most were conducted in the United States and within the past decade. SOE was high for physical activity‐only interventions delivered in schools with home involvement or combined diet–physical activity interventions delivered in schools with both home and community components. SOE was moderate for school‐based interventions targeting either diet or physical activity, combined interventions delivered in schools with home or community components or combined interventions delivered in the community with a school component. SOE was low for combined interventions in childcare or home settings. Evidence was insufficient for other interventions. In conclusion, at least moderately strong evidence supports the effectiveness of school‐based interventions for preventing childhood obesity. More research is needed to evaluate programmes in other settings or of other design types, especially environmental, policy and consumer health informatics‐oriented interventions.     

Is weight regain after bariatric surgery associated with psychiatric comorbidity? A systematic review and meta‐analysis

Bariatric surgery has been recognized as the gold standard treatment for severe obesity. Although postbariatric surgery patients usually achieve and maintain substantial weight loss, a group of individuals may exhibit weight regain. Several factors are proposed to weight regain, including psychiatric comorbidity. The objective of the study is to conduct a systematic review and meta‐analysis of studies investigating the relationship between psychiatric comorbidity and weight regain. A systematic review through PubMed, Web of Science, Cochrane Library, Scopus, and PsycINFO was performed, following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA). After a stepwise selection, 13 articles were included in the qualitative analysis and 5 were included for a meta‐analysis. Women was majority in most of the studies (87.6%), and a bypass procedure was the bariatric intervention most evaluated (66.8%), followed by gastric banding (32.1%) and sleeve (1.1%). Higher rates of postbariatric surgery eating psychopathology were reported in patients with weight regain. However, the association between general psychopathology and weight regain was not consistent across the studies. In the meta‐analysis, the odds of eating psychopathology in the weight regain group was higher compared with the nonweight regain group (OR = 2.2, 95% CI 1.54‐3.15). Postbariatric surgery eating psychopathology seems to play an important role in weight regain.     

Does intentional weight loss improve daytime sleepiness? A systematic review and meta‐analysis

Obesity is associated with excessive daytime sleepiness, but its causality remains unclear. We aimed to assess the extent to which intentional weight loss affects daytime sleepiness. Electronic databases were searched through 24 October 2016. Studies involving overweight or obese adults, a weight loss intervention and repeated valid measures of daytime sleepiness were included in the review. Two independent reviewers extracted data on study characteristics, main outcome (change in daytime sleepiness score standardized by standard deviation of baseline sleepiness scores), potential mediators (e.g. amount of weight loss and change in apnoea–hypopnoea index) and other co‐factors (e.g. baseline demographics). Forty‐two studies were included in the review. Fifteen before‐and‐after studies on surgical weight loss interventions showed large improvements in daytime sleepiness, with a standardized effect size of ?0.97 (95% confidence interval [CI] ?1.21 to ?0.72). Twenty‐seven studies on non‐surgical weight loss interventions showed small‐to‐moderate improvement in daytime sleepiness, with a standardized effect size of ?0.40 (95%CI ?0.52 to ?0.27), with no difference between controlled and before‐and‐after studies. We found a nonlinear association between amount of weight loss and change in daytime sleepiness. This review suggests that weight loss interventions improve daytime sleepiness, with a clear dose–response relationship. This supports the previously hypothesized causal effect of obesity on daytime sleepiness. It is important to assess and manage daytime sleepiness in obese patients.     

Is COPD associated with increased mortality and morbidity in hospitalized pneumonia? A systematic review and meta‐analysis

This review aimed to investigate whether chronic obstructive pulmonary disease (COPD) is associated with increased mortality and morbidity in patients hospitalized with community‐acquired pneumonia (CAP). EMBASE, PubMed and Web of Science were searched for cohort studies and case–control studies investigating the impact of COPD on CAP. The primary outcome was all‐cause mortality, and secondary outcomes included length of hospital stay, intensive care unit (ICU) admission and need for mechanical ventilation. Methodological quality was assessed using the Newcastle–Ottawa Scale. The Mantel–Haenszel method and inverse variance method were used to calculate pooled relative risks (RRs) and mean differences (MD), respectively. Eleven studies (nine cohort studies and two case–control studies), involving 257 958 patients, were included. The overall methodological quality was high. COPD was not associated with increased mortality in hospitalized CAP patients (RR, 1.20; 95% confidence interval (CI): 0.92–1.56; P = 0.19; I² = 55%) in cohort studies, and was associated with reduced mortality in case–control studies (RR, 0.82; 95% CI: 0.74–0.90; P < 0.0001; I² = 80%). COPD was not associated with longer hospital stay (MD, 0.11; 95% CI: ?0.42 to 0.64; P = 0.68; I² = 21%), more frequent ICU admission (RR, 0.97; 95% CI: 0.70–1.35; P = 0.87; I² = 65%), and more need for mechanical ventilation (RR 0.91, 95% CI: 0.71–1.16; P = 0.44; I² = 4%).The current available evidence indicates that COPD may not be associated with increased mortality and morbidity in patients hospitalized with CAP. This conclusion should be re‐evaluated by prospective population‐based cohort studies.     

Can we safely recommend gestational weight gain below the 2009 guidelines in obese women? A systematic review and meta‐analysis

A systematic review was conducted to determine the risk of adverse pregnancy outcomes with gestational weight gain (GWG) below the 2009 Institute of Medicine guidelines compared with within the guidelines in obese women. MEDLINE, Embase, Cochrane Register, CINHAL and Web of Science were searched from 1 January 2009 to 31 July 2014. Quality was assessed using a modified Newcastle–Ottawa scale. Three primary outcomes were included: preterm birth, small for gestational age (SGA) and large for gestational age (LGA). Eighteen cohort studies were included. GWG below the guidelines had higher odds of preterm birth (adjusted odds ratio [AOR] 1.46; 95% confidence interval [CI] 1.07–2.00) and SGA (AOR 1.24; 95% CI 1.13–1.36) and lower odds of LGA (AOR 0.77; 95% CI 0.73–0.81) than GWG within the guidelines. Across the three obesity classes, the odds of SGA and LGA did not show any notable gradient and remained unexplored for preterm birth. Decreased odds were noted for macrosomia (AOR 0.64; 95% CI 0.54–0.77), gestational hypertension (AOR, 0.70; 95% CI 0.53–0.93), pre‐eclampsia (AOR 0.90; 95% CI 0.82–0.99) and caesarean (AOR 0.87; 95% CI 0.82–0.92). GWG below the guidelines cannot be routinely recommended but might occasionally be individualized for certain women, with caution, taking into account other known risk factors.     

Can procalcitonin tests aid in identifying bacterial infections associated with influenza pneumonia? A systematic review and meta‐analysis

Objective To summarize evidence for the diagnostic accuracy of procalcitonin (PCT) tests for identifying secondary bacterial infections in patients with influenza. Methods Major databases, including MEDLINE, EMBASE, and the Cochrane Library, were searched for studies published between January 1966 and May 2009 that evaluated PCT as a marker for diagnosing bacterial infections in patients with influenza infections and that provided sufficient data to construct two‐by‐two tables. Results Six studies were selected that included 137 cases with bacterial coinfection and 381 cases without coinfection. The area under a summary ROC curve was 0·68 (95% CI: 0·64–0·72). The overall sensitivity and specificity estimates for PCT tests were 0·84 (95% CI: 0·75–0·90) and 0·64 (95% CI: 0·58–0·69), respectively. These studies reported heterogeneous sensitivity estimates ranging from 0·74 to 1·0. The positive likelihood ratio for PCT (LR+ = 2·31; 95% CI: 1·93–2·78) was not sufficiently high for its use as a rule‐in diagnostic tool, while its negative likelihood ratio was reasonably low for its use as a rule‐out diagnostic tool (LR? = 0·26; 95% CI: 0·17–0·40). Conclusions Procalcitonin tests have a high sensitivity, particularly for ICU patients, but a low specificity for identifying secondary bacterial infections among patients with influenza. Because of its suboptimal positive likelihood ratio and good negative likelihood ratio, it can be used as a suitable rule‐out test but cannot be used as a standalone rule‐in test.     

Is parity a risk factor for excessive weight gain during pregnancy and postpartum weight retention? A systematic review and meta‐analysis

The aim of this study was to systematically review and meta‐analyse the associations between parity, pre‐pregnancy body mass index (BMI), gestational weight gain (GWG) and, when included, postpartum weight retention (PPWR). Papers reporting associations between parity and BMI and/or GWG in adult women were eligible: 2,195 papers were identified, and 41 longitudinal studies were included in the narrative synthesis; 17 studies were included in a meta‐analysis. Findings indicated that parity was associated positively with pre‐pregnancy BMI. In contrast, the role of parity in GWG was less clear; both positive and negative relationships were reported across studies. Parity was not associated directly with PPWR. This pattern of results was supported by our meta‐analysis with the only significant association between parity and pre‐pregnancy BMI. Overall, parity was associated with higher pre‐pregnancy BMI; however, the role of parity in GWG and PPWR remains unclear, and it is likely that its influence is indirect and complex. Further research to better understand the contribution of parity to maternal obesity is warranted.     

Is there a relationship between obesity and tooth loss and edentulism? A systematic review and meta‐analysis

This study conducted a systematic review to assess the bi‐directional association between tooth loss/edentulism and obesity. Electronic searches were performed in four different databases. Observational studies that tested associations between tooth loss/edentulism and obesity as either exposures or outcomes were included. Additionally, meta‐analyses, funnel plots and sensitivity analyses were conducted to synthesize the evidence. A total of 549 articles were identified in the electronic database search. Out of which, 16 studies were included within the meta‐analyses: 75% considered tooth loss/edentulism as exposure and obesity as outcome, whereas 25% alternatively considered obesity as exposure and tooth loss/edentulism as outcome. Pooled estimates showed that obese individuals had 1.49 (95%CI 1.20–1.86) and 1.25 (95%CI 1.10–1.42) times higher odds of having any tooth loss and edentulism, respectively. Alternatively, when tooth loss or edentulism were considered as exposures, individuals with any tooth loss had 1.41 (95%CI 1.11–1.79) times higher odds for obesity, while edentates had even higher odds (OR 1.60; 95%CI 1.29–2.00). The results indicate a bi‐directional association between tooth loss and obesity. Considering that all selected studies were of cross‐sectional study design limiting inferences on temporality, longitudinal prospective studies are required to test the causal relationship between tooth loss/edentulism and obesity or vice a versa. © 2016 World Obesity